Dimerized isobutene: An alternative to MTBE

Table 2
Published kinetic studies on the oligomerization of isobutene
Catalyst	Conversion and selectivity	Temperature, °C	Solvent	Remarks	Ref.
Amberlyst-15	Selectivity: see Fig. 5	0–80	None or hexane– pentane	Reaction scheme and kinetic modeling	6
Amberlyst-15	Conversion: 60–68%	125	H2O–TBAa	Co-joint production of TBA and dimer	8
	Selectivity: >90%
Amberlyst-15	Yield: 99%		Isooctane–TBA	Uses TBA as a starting material. With out dilution, yield is only 30%	9
Amberlyst-15, Amberlyst-35		75	MeOH–MTBE (MeOH/isobutene= 0.2–0.6)	Co-joint production of MTBE and dimer. Dimer selectivity depends on MeOH/isobutene ratio	10
Lewatit K2631		40–80	MeOH–MTBE	Kinetic model	19
Other catalysts
SPA	Selectivity: 66.2%	160–210	Heavy paraffins (octane): 25%	Using solvent increases selectivity from 56 to 66.2%	11, 12 13
Aluminosilicate (Si/Al = 60–90)	Conversion: 88% Selectivity: 85%	150
aTBA = tert-butyl alcohol